Data labels not working on non zerobased bar charts

[filipfloden]

Description

When using a bar chart, data labels are not working/supported on bars that are non zerobased, i.e., has a start and end value.

Steps to check or reproduce

Turn on labels on a bar chart that has non zerobased values. Example code below.

var chart = bb.generate({
  data: {
    columns: [
	["data1", [50, 100], [100, 250], 100, 400, 150, 250],
    ],
    type: "bar", 
    labels: {
	format(value, id, index) {
		return value
	}
     }
  },
  bar: {
    width: {
      ratio: 0.5
    }
  },
  bindto: "#barChart_1"
});

[netil]

@filipfloden thanks for the report.
There's one more issue on this, which what is the label text for those ranged values?
ex. [50, 100] --> 100? or 50~100?

[filipfloden]

@netil In my specific scenario it would be preferable with [50, 100] --> 100.
But since tooltips display it as [50, 100] --> 50~100 I think it's reasonable to show the label in the same way.
If both are possible with an option that would be great.

Thank you for the response.

[bj00rn]

@netil IMHO ideally the label format function should be called once with [start, end] to allow for custom format logic. I think this reasoning applies to tooltip format function as well. Maybe this is a non-trivial change though

[netil]

ideally the label format function should be called once

The fix will not call data.labels.format multiple times.
It will pass array value for ranged values as argument.

data: {
  labels: {
    format(value, id, index) {
         // for ranged data, the `value` is array
    }
  }
}